Data previewing before recalling large data files

ABSTRACT

Techniques for providing data preview before recalling large data files are disclosed. In one aspect, a data file is made accessible while being offline by converting the data file from a native format to a preview format, storing the data file in the preview format in a primary storage that is locally available and moving, after the conversion to the preview format, the data file in the native format to a secondary storage. When a viewing request is received for the data file, the data file in the preview format is displayed to fulfill the viewing request.

CROSS-REFERENCE TO RELATED APPLICATION(S)

This application is a Continuation of U.S. application Ser. No.16/169,978 filed on Oct. 24, 2018, which is a Continuation of U.S.application Ser. No. 13/801,625 filed on Mar. 13, 2013 (now U.S. Pat.No. 10,157,184), which claims priority to and the benefit of U.S.Provisional Application No. 61/618,039, filed Mar. 30, 2012, all ofwhich are hereby incorporated by reference in their entireties herein.

BACKGROUND

A primary copy of data is generally a production copy or other “live”version of the data which is used by a software application and isgenerally in the native format of that application. Primary copy datamay be maintained in a local memory or other high-speed storage devicethat allows for relatively fast data access if necessary. Such primarycopy data is typically intended for short term retention (e.g., severalhours or days) before some or all of the data is stored as one or moresecondary copies, for example, to prevent loss of data in the event aproblem occurred with the data stored in primary storage.

To protect primary copy data or for other purposes, such as regulatorycompliance, secondary copies (alternatively referred to as “dataprotection copies”) can be made. Examples of secondary copies include abackup copy, a snapshot copy, a hierarchical storage management (“HSM”)copy, an archive copy, and other types of copies.

A backup copy is generally a point-in-time copy of the primary copy datastored in a backup format as opposed to in native application format.For example, a backup copy may be stored in a backup format that isoptimized for compression and for efficient long-term storage. Backupcopies generally have relatively long retention periods and may bestored on media with slower retrieval times than other types ofsecondary copies and media. In some cases, backup copies may be storedat an offsite location.

After an initial, full backup of a data set is performed, periodic,intermittent, or continuous incremental backup operations may besubsequently performed on the data set. Each incremental backupoperation copies only the primary copy data that has changed since thelast full or incremental backup of the data set was performed. In thisway, even if the entire set of primary copy data that is backed up islarge, the amount of data that must be transferred during eachincremental backup operation may be significantly smaller, since onlythe changed data needs to be transferred to secondary storage. Combined,one or more full backup and subsequent incremental copies may beutilized together to periodically or intermittently create a syntheticfull backup copy. More details regarding synthetic storage operationsare found in commonly-assigned U.S. patent application Ser. No.12/510,059, entitled “Snapshot Storage and Management System withIndexing and User Interface,” filed Jul. 27, 2009, now U.S. Pat. No.7,873,806, which is hereby incorporated by reference herein in itsentirety.

An archive copy is generally a copy of the primary copy data, buttypically includes only a subset of the primary copy data that meetscertain criteria and is usually stored in a format other than the nativeapplication format. For example, an archive copy might include only thatdata from the primary copy that is larger than a given size threshold orolder than a given age threshold and that is stored in a backup format.Often, archive data is removed from the primary copy, and a stub isstored in the primary copy to indicate its new location. When a userrequests access to the archive data that has been removed or migrated,systems use the stub to locate the data and often make recovery of thedata appear transparent, even though the archive data may be stored at alocation different from the remaining primary copy data.

Archive copies are typically created and tracked independently of othersecondary copies, such as other backup copies. For example, to create abackup copy, the data storage system transfers a secondary copy ofprimary copy data to secondary storage and tracks the backup copy usinga backup index separate from the archive index. To create an archivecopy, a conventional data storage system transfers the primary copy datato be archived to secondary storage to create an archive copy, replacesthe primary copy data with a stub, and tracks the archive copy using anarchive index. Accordingly, the data storage system will transfer twoseparate times to secondary storage a primary copy data object that isboth archived and backed-up.

Since each transfer consumes network and computing resources, when thetransfers are taking place, the data storage system may not be able todevote such resources to other tasks. Moreover, the data storage systemis required to devote resources to maintaining each separate index. Insome cases, the archive index may be unaware of the other secondary copyand the other secondary index may be unaware of the archive copy, whichmay lead to further inefficiencies. Moreover, in some cases, in theevent that an archive copy is moved or transferred (e.g., to anothertier of secondary storage), the archive index may not be able to beupdated to reflect the move or transfer. In such cases, the data storagesystem may be unable to use the stub to locate the archived data object.

In some operational scenarios, a user may want to browse through filesto either take a quick look at the content or identify a particular filethat the user is interested in, before the user decides to recall theentire file from a secondary backup or an archive, or open the file forreading or writing using the native application for the file.

Recently, Apple Computers has introduced a facility called “Quick Look”in their computer products. Quick Look allows users to look at thecontents of a file in a finder application window at full or near-fullsize resolution, depending on the size of the document relative to thedesktop. Quick Look allows viewing of files in different formats such asPDFs and Microsoft Word, Excel, and PowerPoint file formats. While QuickLook allows quick navigation through various files, no storageefficiencies are gained by using the Quick Look format.

Another problem relates to data storage on mobile devices. Often, datastorage on mobile devices is not optimized. Since mobile devices oftenhave limited storage capacity, such lack of optimization affectsperformance of the device, affects the user experience, etc.

The need exists for systems and methods that overcome the aboveproblems, as well as systems and methods that provide additionalbenefits. Overall, the examples herein of some prior or related systemsand methods and their associated limitations are intended to beillustrative and not exclusive. Other limitations of existing or priorsystems and methods will become apparent to those of skill in the artupon reading the following detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram illustrating an example of suitableinformation management environment in which aspects of the inventivesystem may operate.

FIG. 2 illustrates examples of production and non-production data thatmay be processed by the information management environment of FIG. 1.

FIG. 3 is a block diagram illustrating one example of a hierarchicalarrangement of resources for the information management system of FIG.1, including information management cells.

FIG. 4 is a block diagram illustrating an example of resources formingan information management cell.

FIG. 5 is an example screen shot showing files available to a user.

FIG. 6 is an example of menu options available to a user for interactingwith a stored file.

FIG. 7 is an example data structure used for storage of preview files.

FIG. 8 is a flow chart representation of a process of providing offlineaccess to a data object.

FIG. 9 is a flow chart representation of a process of managing storagecapacity on a computer.

FIG. 10 is a flow chart representation of a process of synchronizingfiles stored on a user device.

FIG. 11 is a flow chart representation of a smart archiving processimplementable on a mobile device.

DETAILED DESCRIPTION

The techniques disclosed in this document are useful, in one aspect, insolving the above-discussed problems related to browsing through largedata files before recalling the data files from a secondary storage. Inanother aspect, the disclosed techniques can be used to convert largedata files from their native format (e.g., an MPEG (Moving PicturesExpert Group) video file, or a PowerPoint file, etc,) to a previewformat. The converted preview format copy, for example, may requiresignificantly lower storage space and require less bandwidth to transferbetween devices. In some implementations, the converted preview formatcopy may disable the ability to select and copy text or images from thefile, but may still allow a low-resource way for a user to browsethrough the content of the file. When some of the files that the userbrowses may be relatively large and may be archived in a secondarystorage, a user's browsing through such files may use network resourcessuch as Input/Output bandwidth and processing power. The use of filecopies in a preview format, also called stub files, in one aspect,reduce the amount of computational resources needed for a user's filebrowsing operation.

The headings provided herein are for convenience only and do notnecessarily affect the scope or meaning of the disclosure.

Overview

A software, firmware, and/or hardware system for facilitating datapreviewing before recalling large data files are disclosed. Alsodisclosed a software, firmware, and/or hardware system to keep devices“clean” by archiving or moving to secondary storage unused data andapplications.

Various examples of the techniques will now be described. The followingdescription provides specific details for a thorough understanding andenabling description of these examples. One skilled in the relevant artwill understand, however, that the invention may be practiced withoutmany of these details. Likewise, one skilled in the relevant art willalso understand that the invention may include many other obviousfeatures not described in detail herein. Additionally, some well-knownstructures or functions may not be shown or described in detail below,so as to avoid unnecessarily obscuring the relevant description.

The terminology used below is to be interpreted in its broadestreasonable manner, even though it is being used in conjunction with adetailed description of certain specific examples of the invention.Indeed, certain terms may even be emphasized below; however, anyterminology intended to be interpreted in any restricted manner will beovertly and specifically defined as such in this Detailed Descriptionsection.

Information Management Environment

Aspects of the technologies described herein may be practiced in aninformation management environment 100, which will now be describedwhile referencing FIG. 1. As shown in FIG. 1, the environment 100includes multiple computing devices that execute numerous softwareapplications to facilitate the operations of an organization (ormultiple affiliated organizations), such as a household, corporation orother business entity, a non-profit organization, an educationalinstitution, or a governmental agency. The computing devices may includeone or more: servers 105 (such as mail servers, file servers, databaseservers, print servers, and web servers), personal computers 110,workstations 115, or other types of fixed computing systems such asmainframe computers and minicomputers (not shown). The servers 105 mayinclude network-attached storage (NAS) filers.

The environment 100 may include virtualized computing resources, such asa virtual machine 120 provided to the organization by a third-partycloud service vendor or a virtual machine 125 running on a virtualmachine host 130 operated by the organization. For example, theorganization may use one virtual machine 125A as a database server andanother virtual machine 125B as a mail server. The environment 100 mayalso include mobile or portable computing devices, such as laptops 135,tablet computers 140, personal data assistants 145, mobile phones 152(such as smartphones), and other mobile or portable computing devicessuch as embedded computers, set top boxes, vehicle-mounted devices,wearable computers, etc.

Of course, other types of computing devices may form part of theenvironment 100. As part of their function, each of these computingdevices creates, accesses, modifies, writes, and otherwise usesproduction copies of data and metadata that are typically stored in apersistent storage medium having fast I/O times. For example, eachcomputing device may regularly access and modify data files and metadatastored on semiconductor memory, a local disk drive or a network-attachedstorage device. Each of these computing devices may access data andmetadata via a file system supported by an operating system of thecomputing device.

The environment 100 may also include hosted services 122 that providevarious online services to the organization or its constituent members(e.g., the organization's departments, employees, independentcontractors, etc.) such as social networking services (e.g., Facebook,Twitter, Pinterest), hosted email services (e.g., Gmail, Yahoo Mail,Hotmail), or hosted productivity applications or other hostedapplications (e.g., Microsoft Office 365, Google Docs, Salesforce.com).Hosted services may include software-as-a-service (SaaS),platform-as-a-service (PaaS), application service providers (ASPs),cloud services, and all manner of delivering computing or functionalityvia a network. As it provides services to users, each hosted service maygenerate additional “hosted data and metadata” that is associated witheach user. For example, Facebook may generate and store photos, wallposts, notes, videos, and other content that are associated with aparticular Facebook user's account.

The organization directly or indirectly employs an informationmanagement system 150 to protect and manage the data and metadata usedby the various computing devices in the environment 100 and the data andmetadata that is maintained by hosted services on behalf of usersassociated with the organization. One example of an informationmanagement system is the CommVault Simpana system, available fromCommVault Systems, Inc. of Oceanport, N.J. The information managementsystem creates and manages non-production copies of the data andmetadata to meet information management goals, such as: permitting theorganization to restore data, metadata or both data and metadata if anoriginal copy of the data/metadata is lost (e.g., by deletion,corruption, or disaster, or because of a service interruption by ahosted service); allowing data to be recovered from a previous time;complying with regulatory data retention and electronic discovery(“e-discovery”) requirements; reducing the amount of data storage mediaused; facilitating data organization and search; improving user accessto data files across multiple computing devices and/or hosted services;and implementing information lifecycle management (“ILM”) or other dataretention policies for the organization. The information managementsystem 150 may create the additional non-production copies of the dataand metadata on any suitable non-production storage medium such asmagnetic disks 155, magnetic tapes 160, other storage media 165 such assolid-state storage devices or optical disks, or on cloud data storagesites 170 (e.g. those operated by third-party vendors). Further detailson the information management system may be found in the assignee's U.S.patent application Ser. No. 12/751,850, filed Mar. 31, 2010 entitledDATA OBJECT STORE AND SERVER FOR A CLOUD STORAGE ENVIRONMENT, INCLUDINGDATA DEDUPLICATION AND DATA MANAGEMENT ACROSS MULTIPLE CLOUD STORAGESITES, now U.S. Patent Publication Number 2010/0332456 (attorney docket606928075US2), which is hereby incorporated herein by reference in itsentirety.

FIG. 2 helps illustrates some differences between “production copies” ofdata and metadata and “non-production copies” of data and metadata inthe data management environment 100. As shown, each computing device 205in the environment 100 has at least one operating system 210 installedand one or more applications 215A-D, such as mail server applications,file server applications, mail client applications, databaseapplications, word processing applications, spreadsheet applications,presentation applications, browser applications, mobile applications,entertainment applications, and so on. Each application can access andmodify various production copies of files stored in a production datastorage medium 218, which may be a network attached storage filer orform part of a Hadoop distributed file system, Open VMS file system, orother type of distributed file system, simply by making conventionalfile system calls via the operating system 210, without needing theinformation management system 150 to intervene on behalf of theoperating system or application. The production copies of files mayinclude structured data (e.g., database files), unstructured data (e.g.,documents), and/or semi-structured data, and thus may include one ormore documents 220A-B, spreadsheets 225, presentation documents 230,video files 232, image files 234, email mailboxes 235, html/xml or othertypes of markup language files 222, and/or databases 240. The operatingsystem 210 may also access and modify production copies of files andother data, such as files in a system volume and/or boot volume. Thehosted data and metadata used by a hosted service are also “productioncopies” of data and metadata since the hosted service accesses andmodifies the user's data and metadata as part of its services.Production copies of data may include not only files, but also subsetsof files, each of which a related application 215 or the operatingsystem 210 treats as an independent functional unit, but which is notseparately addressed in the associated file system. For example, asingle email mailbox 235 may include multiple email messages 245A-C,email headers, and attachments. As another example, a single database240 may include multiple tables 255A-C. As used herein, a “data object”refers to both (1) any file that is currently or previously addressableby a file system and (2) a functional subset of such a file that has aparticular function for a related application 215A-D or the operatingsystem 210. Each data object may be further decomposed into one or moredata blocks each of which is a collection of data bits within the dataobject that may not have any particular function for a relatedapplication or the operating system. In addition to data objects, theoperating system 210 and applications 215A-D may also access and modifyproduction copies of metadata, such as boot sectors, partition layouts,file or data object metadata (e.g., file name, file size,creation/modification/access timestamps, file location within a filefolder directory structure, user permissions, owners, groups, accesscontrol lists (“ACLs”)), and system metadata (e.g., registryinformation). In addition to metadata generated by or related to filesystems and operating systems, some applications maintain indices ofproduction metadata for data objects, e.g., metadata associated withindividual email messages. Thus, as shown in FIG. 2, each data objectmay be associated with a production copy of object metadata(“Metal-11”), which may be file system metadata and/orapplication-specific metadata.

The information management system 150 accesses or receives copies of thevarious production copies of data objects and metadata, and via aninformation management operation (such as a backup operation, archiveoperation, or snapshot operation), creates non-production copies ofthese data objects and metadata, often stored in one or morenon-production storage mediums 265 different than the production storagemedium 218 where the production copies of the data objects and metadatareside. A non-production copy of a data object represents the productiondata object and its associated metadata at a particular point in time(non-production objects 260A-C). Since a production copy of a dataobject or metadata changes over time as it is modified by an application215, hosted service 122, or the operating system 210, the informationmanagement system 150 may create and manage multiple non-productioncopies of a particular data object or metadata, each representing thestate of the production data object or metadata at a particular point intime. Moreover, since a production copy of a data object may eventuallybe deleted from the production data storage medium and the file systemfrom which it originated, the information management system may continueto manage point-in-time representations of that data object, even thougha production copy of the data object itself no longer exists.

For virtualized computing devices, such as virtual machines, theoperating system 210 and applications 215A-D may be running on top ofvirtualization software, and the production data storage medium 218 maybe a virtual disk created on a physical medium such as a physical disk.The information management system may create non-production copies ofthe discrete data objects stored in a virtual disk file (e.g.,documents, email mailboxes, and spreadsheets) and/or non-productioncopies of the entire virtual disk file itself (e.g., a non-productioncopy of an entire .vmdk file).

Each non-production object 260A-C may contain copies of or otherwiserepresent more than one production data object. For example,non-production object 260A represents three separate production dataobjects 255C, 230 and 245C (represented as 245C′, 230′ and 245′,respectively). Moreover, as indicated by the prime mark (′), anon-production object may store a representation of a production dataobject or metadata differently than the original format of the dataobject or metadata, e.g., in a compressed, encrypted, deduplicated, orotherwise optimized format. Although FIG. 2 shows that a singleproduction data object (e.g., 255C), and its associated data objectmetadata (e.g., Meta11) are represented by the contents of only a singlenon-production object (e.g., 260A), the entire contents of a singleproduction data object and/or its metadata at a particular point in timemay instead span across numerous non-production objects. Also a singlenon-production object 260 may contain copies of or otherwise representproduction data objects that originated from different computingdevices.

Non-production copies include backup copies, archive copies, andsnapshot copies. Backup copies are generally used for shorter-term dataprotection and restoration purposes and may be in a native applicationformat or in a non-native format (e.g., compressed, encrypted,deduplicated, and/or otherwise modified from the original applicationformat). Archive copies are generally used for long-term data storagepurposes and may be compressed, encrypted, deduplicated and/or otherwisemodified from the original application format. In some examples, when anarchive copy of a data object is made, a logical reference or stub maybe used to replace the production copy of the data object in theproduction storage medium 218. In such examples, the stub may point toor otherwise reference the archive copy of the data object stored in thenon-production storage medium so that the information management systemcan retrieve the archive copy if needed. The stub may also include somemetadata associated with the data object, so that a file system and/orapplication can provide some information about the data object and/or alimited-functionality version (e.g., a preview) of the data object. Asnapshot copy represents a data object at a particular point in time. Asnapshot copy can be made quickly and without significantly impactingproduction computing resources because large amounts of data need not becopied or moved. A snapshot copy may include a set of pointers derivedfrom the file system or an application, where each pointer points to arespective stored data block, so collectively, the set of pointersreflect the storage location and state of the data object at aparticular point in time when the snapshot copy was created. In“copy-on-write”, if a block of data is to be deleted or changed, thesnapshot process writes the block to a particular data storage location,and the pointer for that block is now directed to that particularlocation. The set of pointers and/or the set of blocks pointed to by asnapshot may be stored within the production data storage medium 218.

Non-production copies of a data object or metadata may be distinguishedfrom a production copy of a data object or metadata in several ways.First, a non-production copy of a data object is created to meet thedifferent information management goals described above and is notdirectly used or modified by applications 215A-D, hosted services 122,or the operating system 210. Second, a non-production copy of a dataobject is stored as one or more non-production objects 260 that may havea format different from the native application format of the productioncopy of the data object, and thus often cannot be directly used by thenative application or a hosted service 122 without first being modified.Third, non-production objects are often stored on a non-productionstorage medium 265 that is inaccessible to the applications 215A-Drunning on computing devices and hosted services 122. Also, somenon-production copies may be “offline copies,” in that they are notreadily available (e.g. not mounted tape or disk.) Offline copiesinclude copies of data that the information management system can accesswithout any human intervention (e.g. tapes within an automated tapelibrary, but not yet mounted in a drive), and copies that theinformation management system 150 can access only with at least somehuman intervention (e.g. tapes located at an offsite storage site).

The information management system 150 also generates informationmanagement data 275, such as indexing information, which permit theinformation management system to perform its various informationmanagement tasks. As shown in FIG. 2, a computing device 205 may includeone or more data management agents 280 that provide client-sidefunctions for the information management system.

Information Management System

FIG. 3 shows a hierarchical arrangement of resources that may form aninformation management system 150. As shown, the information managementsystem 150 includes multiple information management cells 350 arrangedin a hierarchy, with some information management cells (e.g., 350D-E)subordinate to other information management cells (e.g., 350B). A globalstorage manager 305, which may form part of a global information cell350 x, manages the overall hierarchy of information management cells byreceiving reports from the various subordinate information managementcells related to the operation of the cells, determining globalinformation management policies in light of received reports, andpushing information management policies towards subordinate cells forimplementation. The global storage manager may also maintain anddisseminate, to the various cells, system-wide information managementdata. A superior information management cell (e.g., 350B), may performsimilar tasks for its subordinate cells (e.g., 350D-E) and/or otherwiseact as an intermediary between the subordinate cells and the globalstorage manager 305.

Information Management Cell

FIG. 4 shows an arrangement of resources that may form an informationmanagement cell 350. As shown, the information management cell includesa storage manager 402, one or more media agents 410A-M, one or morenon-production storage mediums 155-870, one or more computing devices205A-N, and one or more production data storage mediums 218A-N. Outsideof the information management cell are hosted services 122, which mayinteract with media agents 410 and its components, as described furtherherein. In some examples, all or a portion of an information managementcell may be implemented as an object store, as described in assignee'sU.S. patent application Ser. No. 12/751,850 (introduced above).

The storage manager 402 may be a software module or other applicationthat coordinates and controls information management operationsperformed by one or more information management cells 350 to protect andcontrol copies of non-production data objects and metadata. As shown bythe dashed lines 416 and 422, the storage manager may communicate withsome or all elements of the information management cell 350, such as themedia agents 410 and computing devices 205, to initiate and managebackup operations, snapshot operations, archive operations, datareplication operations, data migrations, data distributions, datarecovery, and other information management operations. The storagemanager may control additional information management operationsincluding ILM, deduplication, content indexing, data classification,data mining or searching, e-discovery management, collaborativesearching, encryption, and compression. Alternatively or additionally, astorage manager may control the creation and management of disasterrecovery copies, which are often created as secondary, high-availabilitydisk copies, using auxiliary copy or replication technologies.

The storage manager 402 may include a jobs agent 455, a management agent450, a network agent 445, and an interface agent 460, all of which maybe implemented as interconnected software modules or applicationprograms. The jobs agent 455 monitors the status of informationmanagement operations previously performed, currently being performed,or scheduled to be performed by the information management cell 350. Themanagement agent 450 provides an interface that allows variousmanagement agents 450 in multiple information management cells 350 (orin a global storage manager 305) to communicate with one another. Thisallows each information management cell 350 to exchange statusinformation, routing information, capacity and utilization information,and information management operation instructions or policies with othercells. In general, the network agent 445 provides the storage manager402 with the ability to communicate with other components within theinformation management cell and the larger information managementsystem, e.g., via proprietary or non-proprietary network protocols andapplication programming interfaces (“APIs”) (including HTTP, HTTPS, FTP,REST, virtualization software APIs, cloud service provider APIs, hostedservice provider APIs). The interface agent 460 includes informationprocessing and display software, such as a graphical user interface(“GUI”), an API, or other interactive interface through which users andsystem processes can retrieve information about the status ofinformation management operations or issue instructions to theinformation management cell and its constituent components. The storagemanager 402 may also track information that permits it to select,designate, or otherwise identify content indices, deduplicationdatabases, or similar databases within its information management cell(or another cell) to be searched in response to certain queries.

The storage manager 402 may also maintain information management data,such as a database 465 of management data and policies. The database 465may include a management index that stores logical associations betweencomponents of the system, user preferences, user profiles (that amongother things, map particular information management users to computingdevices or hosted services), management tasks, or other useful data. Thedatabase 465 may also include various “information management policies,”which are generally data structures or other information sources thateach include a set of criteria and rules associated with performing aninformation management operation. The criteria may be used to determinewhich rules apply to a particular data object, system component, orinformation management operation, and may include:

-   -   frequency with which a production or non-production copy of a        data object or metadata has been or is predicted to be used,        accessed, or modified;    -   access control lists or other security information;    -   the sensitivity (e.g., confidentiality) of a data object as        determined by its content and/or metadata;    -   time-related factors;    -   deduplication information;    -   the computing device, hosted service, computing process, or user        that created, modified, or accessed a production copy of a data        object; and    -   an estimated or historic usage or cost associated with different        components.

The rules may specify, among other things:

-   -   a schedule for performing information management operations,    -   a location (or a class or quality of storage media) for storing        a non-production copy,    -   preferences regarding the encryption, compression, or        deduplication of a non-production copy,    -   resource allocation between different computing devices or other        system components (e.g., bandwidth, storage capacity),    -   whether and how to synchronize or otherwise distribute files or        other data objects across multiple computing devices or hosted        services,    -   network pathways and components to utilize (e.g., to transfer        data) during an information management operation, and    -   retention policies (e.g., the length of time a non-production        copy should be retained in a particular class of storage media).

As noted above, each computing device 205 may include one or more datamanagement agents 280. Each data management agent is a software moduleor component that helps govern communications with other systemcomponents. For example, the data management agent receives commandsfrom the storage manager 402 and sends to and receives from media agents410 copies of data objects, metadata, and other payload (as indicated bythe heavy arrows). Each data management agent accesses data and/ormetadata stored in a production data storage medium 218 and arranges orpacks the data and metadata in a certain format (e.g., backup or archiveformat) before it is transferred to another component. Each datamanagement agent can also restore a production copy of a data object ormetadata in a production data storage medium 218 from a non-productioncopy. A data management agent may perform some functions provided by amedia agent, which are described further herein, such as compression,encryption, or deduplication. Each data management agent may bespecialized for a particular application (e.g. a specified datamanagement agent customized to handle data generated or used by Exchangeby Microsoft Corp.). Alternatively or additionally, a more generic datamanagement agent may handle data generated or used by two or moreapplications.

Each computing device 205 may also include a data distribution and livebrowsing client module 405 (herein “distribution client module”). Thedistribution client module 405 is responsible for, inter alia,associating mobile devices and/or hosted service accounts with users ofthe information management system, setting information managementpolicies for mobile and other computing devices, pushing data objects toa distribution module for distribution to other computing devices,providing unified access to a user's data via an interface, andproviding live browsing features. The various functions of thedistribution client module are described in greater detail herein.

A media agent 410, which may be implemented as a software module,conveys data, as directed by the storage manager 402, between acomputing device 205 (or hosted service 122) and one or morenon-production storage mediums 155-870. Each media agent 410 may controlone or more intermediary storage devices 418, such as a cloud server ora tape or magnetic disk library management system, to read, write, orotherwise manipulate data stored in a non-production storage medium155-870. Each media agent 410 may be considered to be “associated with”a storage device and its related non-production storage media if thatmedia agent is capable of routing data to and storing data in thestorage media managed by the particular storage device. A media agentmay communicate with computing devices 205, hosted services 122, storagedevices 418A-D, and the storage manager 402 via any suitablecommunications path, including SCSI, a Storage Area Network (“SAN”), aFiber Channel communications link, or a wired, wireless, or partiallywired/wireless computer or telecommunications network, including theInternet.

To perform its functions, the media agent 410 may include a media filesystem module 425, a data classification module 435, a content indexingmodule 420, a deduplication module 430, an encryption module 475, acompression module 485, a network module 415, a distribution module 490,and a media agent database 440. The media file system module 425 isresponsible for reading, writing, archiving, copying, migrating,restoring, accessing, moving, sparsifying, deleting, sanitizing,destroying, or otherwise performing file system operations on variousnon-production storage devices of disparate types. The media file systemmodule may also instruct the storage device to use a robotic arm orother retrieval means to load or eject certain storage media such as atape.

The network module 415 permits the media agent to communicate with othercomponents within the system and hosted services 122 via one or moreproprietary and/or non-proprietary network protocols or APIs (includingcloud service provider APIs, virtual machine management APIs, and hostedservice provider APIs). The deduplication module 430 performsdeduplication of data objects and/or data blocks to reduce dataredundancy in the cell. The deduplication module may generate and storedata structures to manage deduplicated data objects, such asdeduplication tables, in the media agent database 440. The encryptionmodule 475 performs encryption of data objects, data blocks, ornon-production objects to ensure data security in the cell. Thecompression module 485 performs compression of data objects, datablocks, or non-production objects to reduce the data capacity needed inthe cell.

The content indexing module 420 analyzes the contents of productioncopies or non-production copies of data objects and/or their associatedmetadata and catalogues the results of this analysis, along with thestorage locations of (or references to) the production or non-productioncopies, in a content index stored within a media agent database 440. Theresults may also be stored elsewhere in the system, e.g., in the storagemanager 402, along with a non-production copy of the data objects,and/or an index cache. Such index data provides the media agent 410 oranother device with an efficient mechanism for locating productioncopies and/or non-production copies of data objects that matchparticular criteria. The index data or other analyses of data objects ormetadata may also be used by the data classification module 435 toassociate data objects with classification identifiers (such asclassification tags) in the media agent database 440 (or other indices)to facilitate information management policies and searches of storeddata objects.

The distribution module 490 may be a set of instructions thatcoordinates the distribution of data objects and indices of dataobjects. The distribution may occur from one computing device 205 toanother computing device 205 and/or from hosted services 122 tocomputing devices 205. As a first example, the distribution module maycollect and manage data and metadata from hosted services 122 or mobiledevices 205. As another example, the distribution module may synchronizedata files or other data objects that are modified on one computingdevice so that the same modified files or objects are available onanother computing device. As yet another example, the distributionmodule may distribute indices of data objects that originated frommultiple computing devices and/or hosted services, so a user can accessall of their data objects through a unified user interface or a nativeapplication on their computing device. The distribution module may alsoinitiate “live browse” sessions to permit communications betweendifferent computing devices so that the devices can interchange data andmetadata or so the devices can provide computing resources, such asapplications, to each other. The functions performed by the distributionmodule are described in greater detail herein.

Brief Architectural Overview

A brief overview of certain aspects of the techniques described ingreater detail below is now provided. In some implementations, a user isable to browse through a file system on his computer using a menustructure and user interface (UI) generally supported by his computer(e.g., Windows 7 interface, Apple iOS interface, and so on). Some of thedisplayed files may be stored in a secondary storage or an archive,which may not be on the user's computer, but are accessible elsewhere ona network to which the user's computer is connected. In someimplementations, a visual cue is provided to a user for the user to beable to distinguish between files that are locally present and filesthat have been archived. In some implementations, archived files arereplaced by a locally available “stub file” copy. In someimplementations, the stub file copy is created by converting a file fromits native format to a preview format. The preview format may becustomized to minimize storage requirement at the expense of addedfunctionality such as being able to manipulate text and graphics in thefile. In one aspect, a user is able to quickly view the content of alarge file using the locally stored stub file and then make a decisionabout whether to recall the entire file from the secondary storage;which may take a significant amount of network and computing resources.

Suitable User Interaction

With reference to FIG. 5, an example of a user interface 500 forallowing data preview before recalling large data files is shown. Insome implementations, the user interface 500 is in the form of a folderview, depicting files available in the folder. In the example shown inFIG. 5, three files, 502, 504 and 506 are displayed to a user. The filesmay also show a file type, e.g., .xyz, .ddd and .abc respectively toidentify the file to a user. Other variations of the folder view andfile display are well known in art and are possible, but omitted in thepresent document for brevity. In FIG. 5, files 502, 504, 506 contain anadditional cue, indicating to the user whether the file is available inits native format or in a preview format. A cue may be provided only forstub files (e.g., file in the native format is not available on theprimary storage). Each displayed file icon may include another smallericon (e.g., 508, 510, 512) indicating whether the file is available inits native format or in preview format. For example, 508 indicates thatthe file is not available in the native format while 510, 512 indicatethat the file is available in the native format and locally stored.

In some implementations, audio tone cues are used to indicate suchavailability. For example, when a user moves the cursor over on the fileicon, an audio tone is generated for stub, e.g., files that are notstored locally in their native formats. Various other techniques, e.g.,use of different colors, different sizes, different fonts, etc. are alsopossible to provide audio/visual cues to the user about which files arestored locally and in native file format, and which are stub files,e.g., available from a secondary (or offline) storage and in a previewformat.

When a user interacts with a file (e.g., file 502), a viewer applicationcan be launched. The viewer application may be launched in a separatewindow 514 (e.g., a pop-up window). The viewer application is describedin greater detail elsewhere in this document. The system may activatethe viewer application when the user performs a specific action on thefile icon (e.g., glide, single click, double click, etc.). The pop-upwindow may be an independent application frame with well-knownattributes and controls such as “full page,” “minimize,” “move,”“close,” etc. Alternatively, the pop-up window is a balloon window which(other than below-described content browsing) is not furthermanipulatable by the user.

Preview Client Application

In some implementations, the viewing program used for showing content ofa stub file to a user is operable on a computer platform as a previewclient application. The preview client may be an off-the-shelf browserthat is modified to display the files in their preview format (e.g., aJPEG viewer or an Internet browser). Alternatively, the preview clientmay be a custom viewing application. The preview client application mayprovide a static display of the content of a stub file. In other words,the preview client does not allow interaction with content beingdisplayed. For example when text is displayed as a JPEG or a .bmp file,the preview client may not allow a user to select and copy text orimages embedded within the content. Other image viewing clients may alsobe used (e.g., a TIFF viewer etc.).

In some implementations, the preview client allows some user interactionsuch as page forward/page backward/page skip for efficient navigationthrough file content via the stub file. For example, with the cursor onwindow 514, a user may be able to press page up/page down and receivedifferent content, e.g., different video frames or different pages.

FIG. 6 depicts additional tasks that can be supported for userinteraction and control. In some implementations, while browsing thefolder 500, a user can perform a specific action (e.g., a right click)to open a menu list 600 of possible actions. In some implementations, auser can open additional menu by performing specific actions (e.g.,mouse right click) while having the cursor on the icon 502 or thepreview area 514. The possible menu items (actions) include, forexample, Recall 602, Play 604, Preview 606, and so on.

In some implementations, when a user selects the Recall 602 option, thecomputer system recalls the file to regenerate the file in native fileformat from a secondary storage or archive to the primary storage,thereby making the file available to the user locally and in the nativefile format. If the file is currently not available for recalling, forexample, when the user is not connected to the appropriate network(e.g., a corporate, an intra network or the Internet) an error messageis displayed to the user that the file is currently not available.

In some implementations, the View 604 mode is made available formultimedia files. For example, the selection of View 604 option, whilepreviewing a media file, may result in, first, a recall of the mediafile from a secondary storage and, second, launching of an application(e.g., a media player) in which the media file can be viewed when it isrecalled to the local storage.

In some implementations, the Play 606 option enables a user to put theunderlying content “in motion.” For example, if the underlying contentis a multi-slide presentation, then the selection of play option resultsin an auto-staged playback of the slides in the “preview mode.” Asanother example, in the play mode, pages of a multi-page document may beflipped automatically by the computer system.

In some implementations, the content of a stub file may be displayed tothe user by refreshing content with next pages or next video frames,simply when the user's cursor is on the file icon. In someimplementations, a stub file may be a hypertext markup language (HTML)file that can be viewed using a web browser. Of course, other file typesand viewers may be used, such as the PDF file type and the Adobe Acrobatviewer.

Storage Management

In some implementations, after converting a file from a native format toa preview format, the file in native format is moved to secondarystorage and information about the location in the secondary storage isassociated with the copy in the preview format. The location informationis associated with the preview format file. One of several well knownmechanisms such as the user resource locator (URL) indicator may be usedfor the association.

FIG. 7 depicts an example block diagram representation of the creationof a stub file (or a file in a preview format) from the original file(file in a native format). The system processes file 700 through aconverter 702 that converts the file from its native format to a previewformat (e.g., from PDF to JPEG or from PowerPoint to PNG, etc.) togenerate preview content 706 representation of the file 700. In otherwords, the converter 702 converts the native file to another, lowerresolution format file, where the lower resolution format file containsless data, and thus consumes fewer data storage resources. In someimplementations, the converter 702 may use off-the-shelf technologiessuch as the content-aware format converter by Stellent, a subsidiary ofOracle.

After the file is converted to the preview format, the system transfersthe file in native format by a transfer module 704 to a secondary orarchive storage, as previously described. Based on the transfer, thesystem generates a pointer 708 with information about where thetransferred occurred to, or in other words, the location of the file inthe secondary storage. The pointer 708 is associated with the viewablecontent 706, together representing the stub file 710.

In some implementations, the decision regarding which files to keep onthe local storage and which ones to replace with their stub fileversions is performed using a set of predetermined rules. The rulesinclude, for example, criteria such as archiving least used files, fileslarger than a threshold size, files of a certain type (e.g., mediafiles), files specifically identified by a user for such offlinestorage, files identified by an application as being suitable foroffline storage, etc. A system administrator may be to modify or updatethe predetermined rules. The management of these rules, in one aspect,helps a corporate network strike the balance between storage use of anorganization and response time to a user browsing through files on thecorporate network. In other words, the organization can manage theamount of primary storage data storage required. The system can analyzehistorical trends in data being stored, data storage capacity (primaryand secondary storage), bandwidth capacity for exchanging data files,and other factors. Based on statistical analysis of these historicaltrends, the system may periodically or continuously/dynamically changethe rules to compensate for changes in data storage, data storagecapacity, bandwidth, etc. Further details regarding other rules andprocesses for moving data objects to secondary storage, especially formobile devices, is discussed below.

FIG. 8 is a flow chart representation of a process 800 for providingoffline access to a data file. At 802, the system converts the data filefrom a native format to a preview format. Various encoders exist forconverting files from one format to another. In some implementations,the process 800 may use alternate informative formats as the previewformat. For example, if the file in the native format is a movie file,then the process 800 may acquire a corresponding trailer file for themovie. The process 800 may, e.g., use publically available databasessuch as Internet Movie Database (IMDb) to receive the trailer file, or auser resource link (URL) to the trailer. In one beneficial aspect, thepreview format thus can be selected to provide an “intelligent”condensed version of the data file in the native format, instead of a“machine based” sliced up preview version. In some implementations,files from other data formats (e.g., images, program source codes) etc.could be replaced with other condensed versions such as links or actualfiles of related resources (smaller video clips, Wikipedia pages, etc.).In some implementations, a check is first made to find out whether acondensed or minimized version is available. If there is a minimizedversion of the same file or document available elsewhere (in the systemor in the Internet), the process 800 could replace the original nativeformat data file with the minimized version. When retrieving, the usercould watch the movie trailer first, for example, instead of usingsystem resource to retrieve the entire movie file.

At 804, the system stores the data file in the preview format in primarystorage. At 806, after converting the file to the preview format, thesystem moves the data file in native format to secondary storage,provide a link to it, and updates the data structure reflecting the newlocation of the native format in secondary storage. In this context,“moving” includes copying and then deleting from the primary storage.

At 808, the system, at some later time, receives a viewing request forthe data file. At 810, if the file to be viewed as located in primarystorage, the data file is displayed in the preview format to fulfill theviewing request. As previously discussed, in some embodiments, thepreview format comprises a picture encoding format such as a JPEG image,or a bitmap format or a GIF (graphics intermediate format) image or aPNG (portable network graphics) image, and so on. At 818, if the filerequested is the native format file, then the system accesses the datastructure to identify the location of the native format file insecondary storage, and retrieves it for display or to be provided to theuser.

In some implementations, a menu for accessing the data file in thenative format is provided. As previously discussed, in someimplementation an audio or a visual cue is provided to a user toindicate whether or not the file icon being browsed by the user is inthe primary storage. For files that are not stored in the primarystorage but are available by retrieving from a secondary storage, a menumay be provided in some implementations. For example, in someimplementations, a user can access file open menu by right-clicking onthe file icon.

As previously discussed, the process 800 may include a resource locatorwith the data object stored in the preview format. The resource locatoris, e.g., in the URL format, indicating the location in the secondarystorage of the native format data object. When the user selects to loadthe image in the native format, then access to the data object may beprovided using the resource locator, using one of several well knownetwork file interface schemes.

While the larger, native format file is generally described herein asbeing stored on the secondary storage, while the stub is stored onprimary storage, the two may be stored together, within a single file.Thus, in an alternative embodiment, a single container file may includethe initial preview file, followed by the native format file. A headermay be provided in the container file to describe the contents, formatand extends (e.g. size) of the embedded preview and native format files.The information management system may manage the container file as asingle file, while the file system of a computing device may view thetwo files independently.

By embedding both preview and native format files within a containerfile, storage management efficiencies may be obtained. Further, such acontainer file may allow both the preview and native format files to bemoved from primary storage to secondary storage. The stub describedherein may link or point to the preview file within the container file,and it is this preview file that is returned by accessing the stub.However, with further input by the user, the system can retrieve thenative format file for the user.

Forward Compatibility with Newer File Formats

When new file formats are introduced (e.g., newer video file formats orfiles generated by new releases of application programs), the converter702 may simply be updated to add a module that is responsive to the newfile format and is able to convert the new file format to a previewformat such as a bitmap or a PNG format file.

Multimedia File Handling

It is well known that multimedia files, especially video files, oftenoccupy a large amount of storage space, compared to documents andspreadsheets. In some implementations, the system replacesabove-discussed pointer 708 with a list of pointers, with each pointerin the list pointing to a next section (e.g., a next independentlydecodable video frame or group of frames) of the stored video file. Inone aspect, such as facility enables random access within a long videofile and allows a user to recall a portion of a video file that is ofinterest. In other words, “bookmarks” may be provided and displayed toaccess sections or portions of the video file. In some embodiments, avideo file in the native format (e.g., an mp4 video file) may beconverted into its stub format by simply clipping the video file tofirst few seconds or by sampling video frames periodically (e.g., onceevery second). It will be appreciated that such techniques beneficiallywould result in a considerable reduction in the storage space needed forthe stub file, compared to the original file, while still providing auser the ability to preview content of the file.

Mobile Computing Environment

In some implementations, a user accesses files (e.g., file folder 500)from a mobile device. A mobile device is often run on battery power andtherefore it may be desirable to customize a user's access to the filesbased on the amount of battery power available to the mobile device. Forexample, in some implementations, when the available batter power (ortime remaining for battery power operation) falls below a threshold, auser may be able to browse through a file 502, 504 or 506 only using alow power option. The low power option may be, e.g., limiting the userto only be able to preview the file in the preview format.

The system described herein can establish certain rules or policies toimplement this functionality on a mobile device. For example, if thebattery-power drops below a 20% threshold, then the system permits themobile device to access only previews. However, when the battery-powereddrops below a 10% threshold, then the system prevents the mobile devicefrom launching resource intensive previews. For example,processor-intensive video decoding may be prohibited and/or access topreviews that require downloads via a wireless link (locally storedpreviews would still be permitted). In other words, any applicationsthat would burden the processor, or consume radio resources, would berationed. Rather than prohibiting or inhibiting such functionality atthese thresholds, the system may instead provide a click through warningfor a user, which would require the user to acknowledge the resourceintensive request before permitting the file to beaccessed/viewed/previewed.

Furthermore, a mobile device typically also has a limited memory orprocessor power for application execution. For example, some mobiledevices may not have a native Office application installed. In suchmobile devices, the only option for a user to be able to view content offiles for which no application is available locally may be to use apreview format. In such implementations, when a user attempts to browsethrough the content of a file, the content is made available only in apreview format.

Typical mobile devices may also be limited by viewing constraints suchas screen resolution, color depth, etc. In some implementations, theconverter 702 selects a target preview format based on such mobiledevice limitations. For example, in some implementations, the converter702 creates multiple resolution images of content pages of a nativeformat file. When the user wishes to browse through suchmulti-resolution content, the system provides or offers a preview filesuitable for the user's mobile device capabilities (e.g., highresolution, low resolution, 18 bit color depth, etc.), also calleddevice resource profile.

Further information regarding data storage methods for mobile devicesmay be found in the assignee's concurrently filed U.S. patentapplication Ser. No. 61/618,506 having Attorney Docket No.60692-8092.US00, to Vibhor et al., entitled “Backup Methods for MobileDevices,” incorporated herein by reference in its entirety.

In some implementations, when a user syncs his user device to acorporate network, a synchronization server automatically stores file inthe right format on the user device. For example, in the case of amobile device that has a 352×240 screen resolution with 16 bit colordepth, a preview file suitable for display on a 352×240 resolution with16 bit color depth is “synched” or stored on the user device.

With reference to FIG. 10, a synchronization server may implement aprocess 1000 as follows. At 1002, the synchronization server obtains aresource profile of a user device (e.g., battery life, displayresolution, available memory, preview applications loaded on the userdevice, etc.). At 1004, based on the resource profile, thesynchronization server then makes file storage decisions regardingmultiple files to be made available to a user of the user device. Foreach file, the synchronization server decides whether to store the filein its native format on the user device or whether to store the file ina preview format on the user device and move the corresponding nativeformat version to a secondary or archive location in the network.

At 1006, when the decision is to store a preview copy on the localstorage of the user device, the synchronization server then decidesattributes of the local copy (e.g., which preview format to use, whatlevel of compression to use, etc.). The synchronization server may makedecisions about the attributes of the local copy based on the resourceprofile of the user device. At 1008, in addition, the synchronizationserver adds metadata to the locally stored preview format file toindicate where to locate the file in its native format and whether thefile is in a preview format or in its native format. To generate thepreview format file, the synchronization server may communicate with theconverter 702, previously discussed.

The above-discussed synchronization process may be run when a portableor mobile device is docked in a device dock or on a periodic basis(e.g., once every week). A user or a system administrator may be able toperform synchronization by running a script or a program. Mobile devicesoften have memory interfaces to attach a removable memory (e.g., securedigital memory card, SIM card, USB flash memory device, etc.). In someimplementations, the removable memory card may be used to transfer filesto/from a user's mobile device and the user's computer. For example,from the desktop, a user may be able to create a “To go” folder and addfiles to the folder by dragging and dropping the files into the folder.The system may then decide, using the previously discussed methodology,whether to store the file in its native format in the “To go” folder orwhether to convert the file to a preview format before copying the fileto the “To go” folder. Once the user has copied all the files he wantsto this folder, the user can simply remove the memory device from thecomputer and attach the memory device to his mobile platform (phone,smartphone, tablet etc.).

The above-discussed system may be expanded to any data or evenapplications. Many current mobile devices, such as tablets and smartphones, have a maximum of 8 GB of storage. The present system mayintelligently archive data and applications by scanning data andapplications on the device and automatically backing up or moving tosecondary storage old and unused data/applications, includingdata/applications that consume power on the device. For example, anelectronic magazine subscription could consume 50 MB per issue,particularly if the magazine has many images. The system canautomatically archive these old subscriptions, such as moving them to asecure cloud storage location associated with the mobile device. Asanother example, the system can scan applications running on the device,including identifying services accessed, to help understand powerconsumption, and compare that to use of those applications by theuser—unused power-hungry applications can be automatically archived tofree up not only data storage on the device, but also free up processingresources and conserve battery power.

In some implementations, a smart archival application may be installedon a mobile device for monitoring memory use by locally stored files.The smart archival application may continuously run in the background ormay periodically wake up and analyze memory usage and whether any localmemory can be freed up by archiving unused files, as described above. Insome implementations, the smart archival application may perform theactual archival task. In some other applications, the housekeeperapplication may only mark files for archival at next availableopportunity (e.g., when the device is being run on AC power or thebattery level is above a threshold such as 80%),

FIG. 11 is a flow chart representation of a process 1100 of performingsmart archiving on mobile devices. At 1102, an archival profile isgenerated for a file. The term “file” may include applications files(e.g., executables, DLLs, etc.). The archival profile may include rulesrelated to when and when not to archive a file. The rules may be basedon criteria such as (a) when was the file used last time, (2) file size,(3) if the file is for a gaming application, then has the user alreadyfinished the level for which the file is used, and so on. For example,files that are not used for a certain period (e.g., 30 days) may beconsidered archival candidates. Similarly, files that are greater than2% of currently available memory or are larger than 50 Mbytes may beconsidered archival candidates. At 1104, a current usage status for afile may be determined using operating system application programmersinterface (APIs). For example, several well known mobile phone operatingsystems provide APIs for querying file usage, access log, etc. At 1106,a decision is taken about whether or not to archive the file based onthe current usage status. For example, the current usage status of thefile indicates that the file meets the archival candidate criteria inthe archive profile, a decision may be taken that the file should bearchived. At 1108, based on availability of resources to perform thearchival of the file, file archival may be performed using a previouslydiscussed technique or alternatively the file may be marked for a laterarchival. For example, when the mobile device is running low on battery(e.g., less than 20%) or when a user is engaged in a CPU-intensiveactivity such as a game, file archiving may be deferred to a later timeby simply marking files for archival. Conclusion

Systems and modules described herein may comprise software, firmware,hardware, or any combination(s) of software, firmware, or hardwaresuitable for the purposes described herein. Software and other modulesmay reside on servers, workstations, personal computers, computerizedtablets, PDAs, smart phones, and other devices suitable for the purposesdescribed herein. Modules described herein may be executed by ageneral-purpose computer, e.g., a server computer, wireless device, orpersonal computer. Those skilled in the relevant art will appreciatethat aspects of the invention can be practiced with othercommunications, data processing, or computer system configurations,including: Internet appliances, hand-held devices (including personaldigital assistants (PDAs)), wearable computers, all manner of cellularor mobile phones, multi-processor systems, microprocessor-based orprogrammable consumer electronics, set-top boxes, network PCs,mini-computers, mainframe computers, and the like. Indeed, the terms“computer,” “server,” “host,” “host system,” and the like, are generallyused interchangeably herein and refer to any of the above devices andsystems, as well as any data processor. Furthermore, aspects of theinvention can be embodied in a special purpose computer or dataprocessor that is specifically programmed, configured, or constructed toperform one or more of the computer-executable instructions explained indetail herein.

Software and other modules may be accessible via local memory, anetwork, a browser, or other application in an ASP context, or viaanother means suitable for the purposes described herein. Examples ofthe technology can also be practiced in distributed computingenvironments where tasks or modules are performed by remote processingdevices, which are linked through a communications network, such as aLocal Area Network (LAN), Wide Area Network (WAN), or the Internet. In adistributed computing environment, program modules may be located inboth local and remote memory storage devices. Data structures describedherein may comprise computer files, variables, programming arrays,programming structures, or any electronic information storage schemes ormethods, or any combinations thereof, suitable for the purposesdescribed herein. User interface elements described herein may compriseelements from graphical user interfaces, command line interfaces, andother interfaces suitable for the purposes described herein.

Examples of the technology may be stored or distributed oncomputer-readable media, including magnetically or optically readablecomputer disks, hard-wired or preprogrammed chips (e.g., EEPROMsemiconductor chips), nanotechnology memory, biological memory, or otherdata storage media. Indeed, computer-implemented instructions, datastructures, screen displays, and other data under aspects of theinvention may be distributed over the Internet or over other networks(including wireless networks), on a propagated signal on a propagationmedium (e.g., an electromagnetic wave(s), a sound wave, etc.) over aperiod of time, or they may be provided on any analog or digital network(packet switched, circuit switched, or other scheme).

Unless the context clearly requires otherwise, throughout thedescription and the claims, the words “comprise,” “comprising,” and thelike are to be construed in an inclusive sense, as opposed to anexclusive or exhaustive sense; that is to say, in the sense of“including, but not limited to.” As used herein, the terms “connected,”“coupled,” or any variant thereof, means any connection or coupling,either direct or indirect, between two or more elements; the coupling orconnection between the elements can be physical, logical, or acombination thereof. Additionally, the words “herein,” “above,” “below,”and words of similar import, when used in this application, refer tothis application as a whole and not to any particular portions of thisapplication. Where the context permits, words in the above DetailedDescription using the singular or plural number may also include theplural or singular number respectively. The word “or,” in reference to alist of two or more items, covers all of the following interpretationsof the word: any of the items in the list, all of the items in the list,and any combination of the items in the list.

The above Detailed Description is not intended to be exhaustive or tolimit the invention to the precise form disclosed above. While specificexamples for the invention are described above for illustrativepurposes, various equivalent modifications are possible within the scopeof the invention, as those skilled in the relevant art will recognize.For example, while processes or blocks are presented in a given order,alternative implementations may perform routines having steps, or employsystems having blocks, in a different order, and some processes orblocks may be deleted, moved, added, subdivided, combined, and/ormodified to provide alternative or subcombinations. Each of theseprocesses or blocks may be implemented in a variety of different ways.Also, while processes or blocks are at times shown as being performed inseries, these processes or blocks may instead be performed orimplemented in parallel, or may be performed at different times. Furtherany specific numbers noted herein are only examples: alternativeimplementations may employ differing values or ranges.

The teachings of the invention provided herein can be applied to othersystems, not necessarily the systems described herein. The elements andacts of the various examples described above can be combined to providefurther implementations of the invention.

Any patents and applications and other references noted above, includingany that may be listed in accompanying filing papers, are incorporatedherein by reference. Aspects of the invention can be modified, ifnecessary, to employ the systems, functions, and concepts of the variousreferences described above to provide yet further implementations of theinvention.

These and other changes can be made to the invention in light of theabove Detailed Description. While the above description describescertain examples of the invention and describes the best modecontemplated, no matter how detailed the above appears in text, theinvention can be practiced in many ways. Details of the system may varyconsiderably in its specific implementation, while still beingencompassed by the invention disclosed herein. As noted above,particular terminology used when describing certain features or aspectsof the invention should not be taken to imply that the terminology isbeing redefined herein to be restricted to any specific characteristics,features, or aspects of the invention with which that terminology isassociated. In general, the terms used in the following claims shouldnot be construed to limit the invention to the specific examplesdisclosed in the specification, unless the above Detailed Descriptionsection explicitly defines such terms. Accordingly, the actual scope ofthe invention encompasses not only the disclosed examples, but also allequivalent ways of practicing or implementing the invention under theclaims.

While certain examples are presented below in certain forms, theapplicant contemplates the various aspects of the invention in anynumber of claim forms. Accordingly, the applicant reserves the right toadd additional claims after filing the application to pursue suchadditional claim forms for other aspects of the invention.

1. A computer-implemented method comprising: based on a data storagecapacity of a computer that comprises one or more hardware processors,determining that a data file is to be converted from a native format toa preview format, wherein the data file in the preview format occupiesless data storage capacity than the data file in the native format;converting the data file from the native format to the preview format;storing the data file in the preview format at a primary data storagedevice of the computer; after the converting of the data file from thenative format to the preview format: copying the data file in the nativeformat from the primary data storage device to a secondary data storagedevice, updating information about a location in the secondary datastorage device of the data file in the native format, deleting the datafile in the native format from the primary data storage device, andwherein the secondary data storage device is offline to the computer;and at the computer, receiving a request for the data file; andresponsive to the request, providing the data file in the preview formatfor display at the computer.
 2. The computer-implemented method of claim1 further comprising: in a view of a folder depicting files available inthe folder, providing a cue that indicates whether the data file isavailable in one of: the preview format and the native format.
 3. Thecomputer-implemented method of claim 1 further comprising: in a view ofa folder depicting files available in the folder, providing a cue thatindicates that the data file is available in the preview format asdistinct from the native format.
 4. The computer-implemented method ofclaim 1 further comprising: providing a view of a folder depicting afirst icon that corresponds to each data file available in the folderand a second and smaller icon that indicates whether the correspondingdata file is available in one of: the preview format and the nativeformat.
 5. The computer-implemented method of claim 1 furthercomprising: providing a view of a folder depicting an icon thatcorresponds to each data file available in the folder, wherein for thedata file in the preview format, a corresponding first icon comprises asecond and smaller icon that indicates that the data file is availablein the preview format as distinct from the native format.
 6. Thecomputer-implemented method of claim 1 further comprising: in a view ofa folder depicting files available in the folder, providing a cue thatindicates that the data file is available in the preview format, asdistinct from the native format, wherein the cue comprises an audiotone.
 7. The computer-implemented method of claim 1, wherein while it isoffline to the computer, the secondary data storage device is notmounted to a drive of the computer.
 8. The computer-implemented methodof claim 1, further comprising: obtaining a resource profile of thecomputer that contains the data storage capacity of the computer.
 9. Thecomputer-implemented method of claim 1, wherein the determining that thedata file is to be converted from the native format to the previewformat is based on one or more predetermined rules.
 10. Thecomputer-implemented method of claim 1 further comprising: regeneratingthe data file from the secondary data storage device to the nativeformat, and storing the data file in the native format at the primarydata storage device.
 11. The computer-implemented method of claim 1,wherein information about locating the data file in the secondary datastorage device is associated with the data file in the preview format.12. A computer-implemented method comprising: obtaining a resourceprofile that comprises primary data storage capacity associated with acomputer, wherein the computer comprises one or more hardwareprocessors; based on the resource profile, determining that a data filestored at a first location at a primary data storage device is to beconverted from a native format to a preview format, wherein the primarydata storage device is one of: accessible to the computer and part ofthe computer, wherein the data file in the preview format occupies lessdata storage capacity than the data file in the native format;converting the data file from the native format to the preview format;storing the data file in the preview format at the primary data storagedevice; after the converting of the data file from the native format tothe preview format: copying the data file in the native format from theprimary data storage device to a secondary data storage device, updatinginformation that indicates a second location of the data file in thenative format at the secondary data storage device as distinct from thefirst location of the data file in the native format at the primary datastorage device, and deleting the data file in the native format from theprimary data storage device, and wherein the secondary data storagedevice is offline to the computer; and at the computer, receiving arequest for the data file; and responsive to the request, providing thedata file in the preview format for display at the computer.
 13. Thecomputer-implemented method of claim 12 further comprising: in a view ofa folder depicting files available in the folder, providing a cue thatindicates that the data file is available in the preview format asdistinct from the native format.
 14. The computer-implemented method ofclaim 12 further comprising: providing a view of a folder depicting afirst icon that corresponds to each data file available in the folderand a second and smaller icon that indicates whether the correspondingdata file is available in the preview format or, alternatively, in thenative format.
 15. The computer-implemented method of claim 12 furthercomprising: providing a view of a folder depicting an icon thatcorresponds to each data file available in the folder, wherein for thedata file in the preview format, a corresponding first icon comprises asecond and smaller icon that indicates that the data file is availablein the preview format as distinct from the native format.
 16. Thecomputer-implemented method of claim 12 further comprising: in a view ofa folder depicting files available in the folder, providing a cue thatindicates that the data file is available in the preview format, asdistinct from the native format, wherein the cue comprises an audiotone.
 17. The computer-implemented method of claim 12, wherein while itis offline to the computer, the secondary data storage device is notmounted to a drive of the computer.
 18. The computer-implemented methodof claim 12 further comprising: recalling the data file from thesecondary data storage device, and storing the data file in the nativeformat at the primary data storage device.
 19. The computer-implementedmethod of claim 12, wherein information about locating the data file inthe secondary data storage device is associated with the data file inthe preview format.
 20. The computer-implemented method of claim 19,wherein the information comprises a resource locator, and wherein theresource locator enables access to the data file in the secondary datastorage device.